不同程度人为干扰对古田山森林群落谱系结构的影响  

Variation in phylogenetic structure of forest communities along a human disturbance gradient in Gutianshan forest, China

作　　者：宋凯[1,2] 米湘成[1] 贾琪[1,3] 任海保[1] Dan Bebber 马克平[1] 

机构地区：[1]中国科学院植物所环境与植被变化国家重点实验室,北京100093 [2]中国科学院研究生院,北京100049 [3]浙江师范大学化学与生命科学学院,浙江金华321004 [4]Earthwatch Institute,Mayfield House,256 Banbury Road,Oxford,OX2 7DE,United Kingdom

出　　处：《生物多样性》2011年第2期190-196,共7页Biodiversity Science

基　　金：Earthwatch Institute Programm"Quantifyand Monitor Carbon Pools and Fluxes to Assess the Impact of Climate Change on Subtropical Forests Under Different Anthropogenic Disturbances"

摘　　要：群落谱系结构包含群落发育的历史信息,能从新的角度反映群落形成的生态过程。作者在浙江古田山自然保护区亚热带常绿阔叶林中选择了人为干扰强度不同的4种群落类型,以20m×20m为研究尺度探讨了不同干扰程度对群落谱系结构的影响。结果表明,人工林(类型I)谱系结构发散;但间伐林(类型II)、自然恢复林(类型III)以及自然老龄林(类型IV)谱系结构聚集,且以类型II和IV聚集度最高。进一步分析不同径级谱系结构发现,在中小径级(DBH≤5cm和5cm<DBH≤10cm),类型II、III、IV群落谱系结构聚集,而类型I群落谱系结构发散;但DBH>10cm时,除了类型IV,其他3种群落都是谱系结构发散,这反映了在恢复早期种子扩散对这些林型群落构建影响较大;而皆伐后的演替和间伐增加了群落生境异质性,生境过滤作用增强,使类型II、III群落中小径级谱系结构表现为聚集;类型IV群落不同径级谱系结构均表现为聚集,可能与其稳定的生境过滤作用有关。Community phylogenetic structure contains information about evolutionary relationships among coexisting species in a community. Studies on community phylogenetic structure provide new insights into ecological processes and the mechanisms underlying community restoration. We compared the phylogenetic structure of forest communities along a human disturbance gradient using data from 12 1-ha plots in secon-dary forests within the Gutianshan National Nature Reserve, Zhejiang Province, China. We found that, at the 20 m×20 m scale, the plantation forest community （I） was phylogenetically overdispersed. Forest communities II （naturally-restored forest 50 years after clear cutting and 20 years after heavy selective cutting）, III （naturally-restored forest 50 years after clear cutting）, and IV （oldgrowth forest） were phylogenetically clustered. Forest types II and IV were the most clustered. We also conducted the same analyses for four forest types grouped into different DBH classes, and found that forests II, III, IV with DBH less than 5 cm and 5–10 cm were phylogenetically clustered, but forest I was overdispersed. In contrast, all the forests with DBH more than 10 cm were phylogenetically overdispersed except the forest IV. Our results suggest that seed dispersal is the main process resulting in phylogenetic overdispersion at early stage of succession, and habitat filtering is main process leading to phylogenetic clustering when habitat heterogeneity increases during succession. Possibly as a result of habitat filtering, forest IV was always phylogenetically clustered regardless of which size class was examined.

关 键 词：群落结构 谱系发散 谱系聚集 径级结构 种子传播 生境过滤 

分 类 号：S718.5[农业科学—林学]